package lab02.test28;

import java.util.InputMismatchException;
import java.util.Scanner;

/**
 * Created by ASUS on 2017/11/13.
 */
public class Test {
    public static void main(String[] args) {
        double radius;
        double area;
        Scanner scanner=new Scanner(System.in);

        try{
            radius=scanner.nextDouble();
            area=3.14*radius*radius;
            System.out.println(area);
        }catch (InputMismatchException e){
            System.out.println("输入的不是double型！！");
        }finally {
            System.out.println("如果出现结果，那么恭喜你，否则，请你再试一次！！");
        }

    }
}
